Samsung SCH-811 Service Manual page 34

6-1-5 Abnormal Key tone
Waveform output
from U102 pin 14, 15, 16
Waveform output
from U102 pin 2, 3?
Waveform applied to
normal key tone?
6-5
Press and key
Yes
Yes
SPK(+), (-)?
Yes
Yes
END
Check U102 pin 14, 15, 16.
No
Replace if required.
Check U102, pin 2, 3 and its
neighboring circuits.
No
Replace if required.
Check U102, R250 and C108, FPC.
No
Replace if required.
No
Replace if required.
SAMSUNG Proprietary-Contents may change without notice
Check SPK.